Inorganic adsorbent materials, such as molecular sieves, zeolites, etc., have long been used to remove constituents from (gaseous and/or liquid) fluids. Zeolites such as zeolites A and X are widely used in desiccating and gas treatment applications.
The use of adsorbent materials in the form of a free flowing particulate (e.g. beads) well known. Such beads typically comprise the adsorbent material in combination with a binder. While inorganic binders are most often used, the use of organic binders in free flowing beads is also known and is of growing interest. Where an organic binder is used, it is naturally desired to minimize the organic content of the bead while maintaining sufficient physical integrity in the bead.
In other instances, the adsorbent may be placed in an organic matrix which is then applied to a surface. For example, in the window spacer structures disclosed in U.S. Pat. Nos. 5,177,916 and 5,255,481, the adsorbent material is loaded into an organic matrix which is then adhered to the spacer. The adsorbent is typically incorporated into the organic matrix by mechanical mixing while the organic matrix material is in a very soft or molten state. It is generally desirable to incorporate as much of the adsorbent as possible per unit of organic matrix so as to enhance the adsorption performance of the adsorbent/organic matrix composite as well as to reduce the cost of the composite in situations where the organic material is more expensive than the adsorbent. Unfortunately, the amount of adsorbent which can be loaded into the composite is often limited by viscosity buildup which occurs during incorporation of the adsorbent as well as by a loss of workability and/or physical integrity in the resulting composite where the composite is applied to a substrate as in the above mentioned window spacer structures.
The organic binder level requirement and/or viscosity buildup associated with commercial adsorbent molecular sieves is generally assumed to be constant and unalterable. While it might be possible to increase the adsorbent loading by developing specialized organic materials or additives, these alternatives are typically expensive. Thus, there is a need for new ways of minimizing organic content adsorbent/organic matrix (binder) compositions, yet with minimal sacrifice of physical integrity and/or workability in the resulting composite.